Horn



July 26, 1927.

T. J; SCQFIELD norm Filed Aug. 7, 1922 2 Sheets-Sheet 2 Patented July 26, 1927.

UNITED STATES PATENT OFFICE. I

THEODORE J. SCOFIELD, F JACKSON, MICHIGAN, ASSIGNOR TO THE SPARKS-WITH- INGTON COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

HORN.

Application filed Auig'ust 7, 1922. Serial No. 580,262.

This invention relates tocertain improvements in motor driven horns adapted to be used as a signal or alarm for automobiles, motor boats, and similar machines.

The main object of the invention'is to produce a simple, powerful and light motor horn at a considerably lower cost of manufacture than has heretofore been practiced, without sacrificing any of the advantages in this class of horn. v a

Other objects and advantages relate to the details of form, construction and arrangement of the parts, all as will more fully appear from the following description, taken in connection with the accompanying drawings, in which Figure l is a longitudinal section of the .horn of my invention.

Figure 2 is a rear View of the horn with the case and end plate removed; I

Figure 3 is a view of the commutator brushes and the means for supporting the same in operative position. v,

Figure fl: is a front view of the horn with the resonator and diaphragm removed.

Figure 5 is a sectional view of the rear diaphragm casing.

Figure 6 is a sectional view thru the post and a commutator-supporting mechanism showing the spring permitting adjustment of the rear case, and the motor shaft.

Figure 7 is a sectional View thru the coil and its supporting cylinder.

The invention, as illustrated. comprises a suitable diaphragm -1- having its marginal portion clamped between the base 2- of a front diaphragm case section 3 and the base of a rear diaphragm case section l, said sections and the diaphragm being secured in cooperative'position in any suitable manner, as by screws '-5 and cooperating nuts 6.

.The front diaphragm case section -8- may carry in the usual manner a resonator -7- of any desired form and shape. 7

The rear diaphragm case section-4 is preferably dished away from the diaphragm, as indicated in Figure 1, to form a dia phragm-vibrating chamber within which the actuator 8 rotates for contact with the wear piece 9 upon the diaphragm to effect vibration of the latter as the former is rotated. The case section -4-, as perhaps best indicated in Figure 5, has its central portion -10- offset or pressed inwardly toward the diaphragm and is formed at an eccentric point with an opening -11 provided with an inwardly projecting annular flange 12- constituting a bearing for the motor shaft 13- which carries the actuator 8 as heretofore referred to. r

This off-set portion or cross bar 10- of the'diaphragm case permits carrying of the bearing 11 forwardly of the plane of the rear wall of the section -4 and toward the diaphragm, so that the armature 14 of the motor may be arranged in close proximity to the diaphragm, and perhaps partially withinthe case section -4e, and between the pole pieces 15.Vand 16, which may be, as shown, struck up from the case section -4: and project rearwardly therefrom, as hereinafter described.

The pole pieces -15- and 16 are preferably of the arcuate form perhaps best illustrated in Figures 4 and 5, and are arranged upon opposite sides of the bearing -12 and comprise portions 17 integrally connecting the pole pieces to'the base of the casesection -l. -Each pole piece includes a substantially straight extension, bracket or lug l8 and 19- respectively projecting laterally from the respective'pole pieces and these extensions in substantially the same direction and in substantial. parallelism with each other and with the cross bar 10- constitute bearing parts or brackets for the field coil 20 which is formed of insulated wire wound around a bar or cylinder 21- disposed between the arms '18 and 19 and secured in,

position in any suitable way as by means of screws ,-22-- projecting thru vopenings in the respective parts 18- and 19-,and screwed into the interiorly threaded portion of the tube or cylinder -21.

Bythis means a rigid support for the field.

coil 20 -2l is provided and the pole pieces for the motor are materially strength ened by the rigid spacing and supporting cylinder 21 20-. The rear-bearing for the motor shaft -13 is formed in a cupshaped cover plate -25 which has a re cessed or dished eccentric portion-4S0- which may be of circular form and covered at its inner side by a disk -23 having its edge secured as by welding to the rear cover plate so as to constitute a rigid portion thereof, and provided with a perforation or opening formed with a surrounding flange 21 constituting a bearing for the anmature shaft. The shaft is adapted to contact at its rear end with the inner surface of the dished portion 60 of the'cap or closure 25 and its adjustment may be'efi'ected by moving said end cap or closure toward or from the diaphragm. The disk 23- may be secured to the cap .25 in any suitable way, as by welding or otherwise. The support for the closure plate 25 is effected thru the medium of a pair of posts 62- and 63+ of similar form and construction, and having their forward ends reduced and threaded and projected thru the base of the case section -4- so that the shoulder -61 at the reduced portion contacts with the outer surface of the case section 1-- and is secured in tight and rigid relation with respect to said section by means of nuts 28 and by this construction the posts becomesubstantially rigid parts projecting from the case section 4 and have their outer ends reduced and threaded and projected through the end cap -25 and secured in proper relation thereto by means of arts about to be described.

he post -62 may be provided with an adjusting and stationing nut -30- threaded onthe rear end of the post and adapted to be positioned upon the interior of the rear cap 25 so as to lock one side of the cap in a pre-determined position, while the nut Q9 threaded on the outer end of said post is adapted to contact with the outer surface. of the cover plate to maintain the same in practically stationary position with res ect to post -62-.

he opposite side of the cap is adjustably supported by means of a spiral spring 31- mounted on 0st 63 and positioned between the en cap 25- and the insulating block 32 also mounted on post -63- and which, as hereinafter described, carries the commutator brushes +33- and -3,1- which are adapted to contact with the commutator -35-- upon the armature shaft -13. By adjusting nut the cover plate or rear cap 25- may be 'moved toward the diaphragm against the action of spring -31- therebyv carrying the armature shaft forwardly to properly position the cam or actuator with respect'to the diaphragm wear piece 9.

For the purpose of holding the armature shaft against rattling, and at all times in substantial contact with the interior of the end cap --25 a spring bar 33 is provided mounted upon one of the posts 62- or 63 at a point upon the interior of the case section 4 and between the case section and one of the nuts 28. and the bar has its intermediate portion bent outwardly toward the diaphragm and its outer end portion bent lengthwise across the actuator 8- and into contact with the end of the armature shaft -13- so as to press said armature shaft toward the interior of the end cap ,25 to hold the same in proper relation against rattling.

The post 63 upon which the spring 31- is mounted has as before stated, mounted thereon an insulating block -32- whlch rests against the shoulder 36 upon the post --62 and is formed as shown in Figure 3, with an opening -37 adapted to fit upon the reduced rear portion of said post, and is held in position against shoulder 36 by means of the spring 31, cap 25 and nut 70-. This insulating block is provided with a laterally extending conduit 38' internally threaded, as indicated by dotted lines in Figure 3, and carries the resilient flexible bars -39- for the commutator brushes, and which bars have perforated ,end portions extending across the conduit 38 with their perforations in alignment with said conduit for the reception of retaining screws 40- which are preferably spaced from the commutator bars 39 by means of U-shaped clips 41 having their flanged edges projecting laterally across the commutator bars 39-- so as to maintain the same in proper position a; when the screws -40. are tightened with relation to the insulating block -32-. The brushes 33 and 34- are preferably carried by the forward end of the bars 39 and may have their inner surfaces of arm arcuate form to substantially fit the commutator, as indicated. The bars -39 in themselves constitute spring members tensioning to hold such brushes in contact with the commutator while efi'ecting proper elec- 0; trical relation.

The motor structure of the horn so far described is preferably encased within a cylindrical casing 42- which may be formed of a single sheet of metal bent into circular form and having its longitudinal edges seamed or otherwise secured together to constitute a closed cylindrical case which is adapted to be fitted over the end cap --25 and brought into engaging relation with the case section -4 which is shown as provided with a reduced shouldered portion -43 about which the casing -42 is adapted to tightly fit, and to which it may be secured in any suitable manner, as by screws (not shown).

It will be noted that this construction'of horn is of very simple character; that it may be formed and assembled in a comparativelv small space, the pole pieces being purposely formed from the rear diaphragm case section, although they may be formed separately therefrom and secured to the case section 4 in any suitable manner, as by screws or. welding. The forward armature 13o shaft bearing is formed in an'inset cross bar integral with the rear diaphragm case section, and the entire supporting mechanism for the rear portion of the motor is providedthru the means of a pair of posts, one of which carries both commutator brushes and which posts are rigidly secured to the rear diaphragm case section. Novel means are provided for adjusting the motor shaft toward and from the diaphragm for effecting proper relation of the actuator with the wear piece 9.

Although I have shown and described a specific structure, form and relation of the parts constituting a preferred embodiment of my invention, it will be obvious that all of the details are not inter-related, and that certain of the details of this invention may be combined with other forms of arrangement of parts, and in other relations, and that various changes and modifications may be made in the details of construction, form and arrangement of the parts, whether related or combined in a single structure, without departing from the invention as set forth in the appended claims.

I claim: I 1. A horn comprising a case section, a pair of posts secured to said case section, and projecting therefrom, an end cap mounted on said posts, an armature shaft journaled in said case section and in said end cap, a commutator on said armature shaft, and a pair of commutator brushes carried by one of said posts for contact with said commutator.

2. A horn comprising a case section, a pair of posts secured to said case section and projecting therefrom, an armature shaft journaled in said case section, a commutator on said armature shaft, an insulating block mounted on one of said posts, a pair of springarms carried by said insulating block, and a pair of brushes carried by said spring arm for contact with said commutator.

8. A. horn comprising a case section, a pair of posts secured to said case section and projecting therefrom, an end cap mounted on said post, an insulating block mounted on one of said. posts, a spring interposed between the insulating block and the end cap, an armature shaft journaled in the case sec tion and end cap, a commutator on said armature shaft, and a pair of brushes carried by said insulating block for contact with said commutator.

4:. A horn comprising a case section, a pair said insulating block for contact with said commutator, and spring means tending to move the armature shaft toward the end cap.

5. A horn comprising a case section, a pair of posts secured to said case section and projecting therefrom, an end cap mounted on said post, an insulating block mounted on one of said posts, a spring interposed between the insulating block and the end cap, an armature shaft ournaled in the case section and end' cap, a commutator on said armature shaft, a pair of brushes carried by said insulating block for contact with said 0011111'3.l1t2tt01,'2l11l a plate bearing against the forward end of said armature shaft and tending to move said shaft toward the end cap.

6. A- horn comprising a case section having a pair of pole pieces struck up therefrom and integral therewith, a lug projecting laterally from each pole piece, a bar carried by the lugs and a field coil carried by said bar.

7. A horn comprising a case section, a diaphragm extending across the case section, pole pieces secured to the case section, ears projecting from the pole pieces in a direction substantially parallel with the diaphragm, a bar carried by the ears and a field coil carried by said bar. I

8. A horn comprising a case section, a diaphragm extending across the case section, pole pieces secured to the case section, ears projecting from the pole pieces in a direction substantially parallel with the diaphragm,

a cross bar connecting said ears, and a field coil mounted on said bar.

9. A horn comprising a front case sect-ion, a cup-shaped rear case section, a diaphragm having its marginal portion clamped between said case sections, said rear case section provided with pole pieces struck up therefrom and integral therewith, and forming a crossbar, and an armature shaft having a bearing with said cross bar.

10. A horn embodying a cup-shaped diaphragm case section having a part of its bottom portion offset forwardly, an armature shaft having a bearing in said forwardly offset portion, an armature mounted on said shaft in such a position that a portion of the armature is forward of the plane of said bottom portion of the diaphragm case section, and pole pieces struck up from said bottom portion at opposite sides of the forwardly offset portion.

11. A horn embodying a cup-shaped diaphragm case section having a part of its bottom portion offset forwardly, an armature shaft having av bearing in said forwardly off-set portion, an armature mounted on said shaft in such a position that a portion of the armature is forward of the plane of said bottom portion of the diaphragm case section, pole pieces struck up from said bottom portion at opposite sides of the forwardly offset portion, lugs extending laterally from the pole pieces, and. a field coil carried by said bar.

12. A horn comprising an armature shaft having a commutator mounted thereon, a case section formed with a bearing for said armature shaft, and a post carried by said case section, an insulating block mounted on said post, a pair of spring arms carried by saidblock, and a brush mounted upon each of said spring arms for contact with said commutator.

13. A horn comprising a case section, a pair of posts secured to said case section and projecting rcarwardly therefrom, an end cap mounted on said posts, one of said mountings being adjustable, an armature shaft having one end journaled in said casing and its other end having athrust bearing in said end cap, means for adjusting the cap along one of said posts, and spring means tending to move a'portion of said cap in a direction away from said case section.

14. A horn comprising a case section, a pair of posts secured to said case section and projecting rearwardly therefrom, an end cap mounted on said posts, one of said mountings being adjust-able, an armature shaft having one end-journaled in said casing, and its other end having a thrust bearing in said end cap, means for adjusting the cap along one of said posts, and spring means tending to move said armature shaft toward said end cap.

In witness whereof I have hereunto set my hand this 29th day of July, 1922.

THEODORE J. SCOFIELD. 

